KRAS and colonic neoplasm: To this end, we utilized the Pan-European Trials in Alimentary Tract Colon Cancers (PETACC-3), a large Phase III randomized trial in which 688 patients with stage II or III CRC were characterized by genomic and mutational analysis, including KRAS and BRAF. Because the mutant Kras allele in the GEMM cohort (KrasLSL-G12D) is a gain-of-function mutation, for the purpose of comparison we considered all KRAS gain-of-function mutations in the PETACC-3 dataset, with the caveat that different types of KRAS mutations potentially have unique biological characteristics (Kirk, 2011).